The present invention relates to a computerized music apparatus which generates musical sound by loading software modules for carrying out various tasks from a secondary storage device into a primary storage device. Further, the present invention relates to a computerized music apparatus which can emulate a tone generating system of existing electronic musical instrument by extended versatility.
There are various types of electronic musical instruments including high performance products and low ability products. The conventional electronic musical instruments employ hardwares which are different a product by product, and usually, their softwares are separately developed as specific ones. Since it is troublesome to independently develop softwares for different instruments, a convenient technique is disclosed in JP-A-3-39995. The technique disclosed in JP-A-3-39995 is such that a model code to specify a desired product is registered by jumper lines or switches. A CPU of the product discriminates the model code, and executes data processing according to the code. Thus, common programs can be used for multiple products different in performance. It is possible to selectively carry out various controls such as an automatic accompaniment function is installed and performed only in a product in which this function is implemented. This function is disabled in another product in which the function is not implemented. However, the technique disclosed in JP-A-3-39995 has a drawback that the control program should be fixed in advance, and it is difficult to modify the program. For example, even if only a part of the software related to the automatic accompaniment function has to be modified, it is not easy to modify only that part. Further, in the prior art, the program commonly used in the products having different performances is stored in a primary storage, so that an unnecessary part of the program may be stored in the primary storage as well. Furthermore, common use of program modules is not considered in the prior art. For instance, many similar programs have been developed separately, and they are not compatible with each other.
Today, various types of electronic musical instruments are put in practical use, and various sound sources (musical tone generators) are known and employed in the instruments. Among current products, there are some electronic musical instruments which use the same sound source commonly. However, most of the instruments generally employ a specific sound source, which is different by a product to product. Thus, configuration of a tone generating system and a data format used in the instruments also vary by a product to product. To eliminate such an inconvenience, and to improve compatibility of the data format of performance data and timbre data, GM (General MIDI) standard is established. For example, an order of timbres specified by codes is defined in the GM standard, and a MIDI apparatus is structured to select a similar timbre even if another timbre code which is not supported in the instrument is specified according to the defined order of the timbres. However, the performance data and the timbre information created for a specific platform are often incompatible in another platform, and sometimes they cannot be reproduced perfectly on another platform. This is caused by incompatibility of a sound source hardware and else. Examples of the incompatibility are listed below:
(a) Musical tone synthesizing method employed in the sound source is different among various products. There are various synthesizing principles such as PCM, FM, and physical model. PA1 (b) Sound effector is not compatible. A sound source may accommodate various effectors such as a tone filter and a reverb circuit. If a sound source lacks the effector, it is difficult to synthesize the same sound as in another instrument. PA1 (c) Type and number of control parameters are not compatible over various sound sources. Even if similar control parameters are used in different platforms, a control range of the parameter may be limited, or cannot be altered at all. PA1 (d) Actual effect corresponding to a parameter is different due to hardware difference between platforms. The actual effect of similar digital filters (e.g. cutoff frequency) may vary over platforms due to difference in the filtering method or dimension of filtering. PA1 (e) Program of CPU to control the sound source is different. The programs may vary in its tone assignment pattern, polyphony for a tone, control timings and so on.
As described above, the conventional electronic musical instruments suffer from a lot of limitations with respect to the hardware and software construction and are poor in compatibility and versatility.